Outside of the Romney campaign, Adelson has spent upwards of $20 million in donations to Republican candidates this election cycle, and almost single-handedly bankrolled Newt Gingrich's rollercoaster primary campaign. CBS pegs him as the biggest super PAC donor of this election cycle.

Adelson mostly avoids the media spotlight, but his rags-to-riches tale reveals some of the reasons as to why he made huge ideological and personal changes through his life.

Adelson's computer trade show, Comdex, became one of the world's largest in the world in the 1980s.

Adelson went on to buy the historic Sands Hotel and Casino in Las Vegas, adding a convention center for the thriving Comdex. Adelson later cashed in on Comdex for $862 million, using the profits to tear down the hotel and rebuild a lavish, Venice-inspired complex.

The Sands Macau is where Adelson made his billions.

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Since the Sands Macau, located in Macau Peninsula, Macau, opened its doors, Adelson's personal wealth has "multiplied more than fourteen times," and "earning roughly a million dollars an hour" after the company went public, The New Yorker reported.

But Adelson has been accused of welcoming prostitutes to the Macau resort.

"Mr. Adelson has always objected to and maintained a strong policy against prostitution on our properties, a fact that Mr Jacobs knows to be true, and any accusation to the contrary represents a reprehensible personal attack on Mr Adelson's character," Adelson and his lawyers said in a statement.

Democrats have begun trying to tear him down over the issue, but their first shot was a big miss.

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The Democratic Congressional Campaign Committee decided to retract statements it had made about Adelson, which linked him to "Chinese prostitution money" that was going to Republican candidates. Adelson's lawyers wrote a letter to the DCCC threatening legal action.

"Mr. Adelson does not tolerate prostitution, let alone, as you have said, make money from it," his attorneys wrote. "The fact is that Mr. Adelson has consistently objected to and maintained a strong policy against prostitution."

But today, Mr. Yang, along with tens of millions of dollars in payments the Sands made through him in China, is a focus of a wide-ranging federal investigation into potential bribery of foreign officials and other matters in China and Macau, according to people with direct knowledge of the inquiries. [...]

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Adelson met his second wife on a blind date.

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Adelson has been married twice, divorcing his first wife, Susan, in the 1980s. He had adopted Susan's three children, two boys and a girl.

He was introduced to his current wife, Dr. Miriam Ochschorn, a divorced doctor from Israel who was working in New York, by a mutual friend. The couple married in 1991.

The billionaire is also a target for lawsuits from both family and friends.

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Adelson has had somewhat of a rough patch with his adopted sons. In 1997, two of Adelson's sons, Mitchell and Gary, sued their father. They alleged that Adelson cheated them out of money by encouraging them to sell their shares of his company without providing full information. They lost the case.

Mitchell and Gary both suffered from drug addiction. In 2005, Mitchell, who was married with three children, died unexpectedly when he was 48, reportedly of a drug overdose.

Now, Adelson donates generously to Jewish organizations.

Adelson gives to the powerful Jewish lobby American Israel Public Affairs Committee, or AIPAC, and the Zionist Organization of America. This year, Adelson pledged an additional $13 million to Taglit-Birthright Israel, an organization that sends young Jews to Israel.

Reportedly, Adelson's stance on Israel became more conservative under the influence of his second wife.

Much of his personal stake in politics comes from a strong opposition to a two-state solution to the Israeli-Palestinian conflict.

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He even appealed to President George W. Bush directly when talks restarted over the issue in 2007.

The Jewish Weekly quoted Adelson as saying "the two-state solution is a stepping stone for the destruction of Israel and the Jewish people." He sees no distinction between the terrorist group Hamas and the Palestinian leadership.

But Adelson's first political contributions actually went to Democrats.

Adelson donated $2,000 to now-Senate Majority Leader Harry Reid in 1989. He also donated $2,000 to Sen. Ted Kennedy in 1993, when he was in an election fight with challenger ... Mitt Romney. But he pretty much stopped donating to Democrats in the 1993 cycle.

The New Yorker reported that as his wealth grew, "he began to favor tax-averse Republican economic policies. He argued to an associate recently, 'Why is it fair that I should be paying a higher percentage of taxes than anyone else?'"

Since Gingrich left the race, Adelson has pledged to spend a possibly "unlimited amount" to get Mitt Romney elected.

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Even though former Republican presidential candidate John McCain blasted Adelson, the casino executive just continued to donate. Adelson has spent more than $20 million in the 2012 election cycle alone.

He told Forbes that he is against the concept, but he'll contribute as long as its legal.

"I'm against very wealthy ­people attempting to or influencing elections," he told Forbes. "But as long as it's doable I'm going to do it. Because I know that guys like Soros have been doing it for years, if not decades. And they stay below the radar by creating a network of corporations to funnel their money. I have my own philosophy and I'm not ashamed of it. I gave the money because there is no other legal way to do it. I don't want to go through ten different corporations to hide my name. I'm proud of what I do and I'm not looking to escape recognition."

The billionaire has also asked Romney to state publicly that Israeli-Palestinian peace talks are a waste of time because the Palestinians are unwilling to make peace, according to the sources—and he wants a firmer commitment from Romney to move the U.S. Embassy in Israel from Tel Aviv to Jerusalem, in what would be a de facto recognition of Israel's annexation of East Jerusalem.

So far, Romney has been hesitant to comply, especially on the Pollard front.

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Adelson joked that he attended Romney's Israel fundraiser to 'get a shwarma sandwich.'

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Adelson remains mostly a mystery.

Adelson says he may write a book one day, but in the meantime The New York Times described him as "hardly a household name. He avoids the limelight and rarely speaks to the press, remaining something of an enigma."

When a reporter introduced himself in Israel, Adelson responded: "Why do you guys keep writing negative things about me?"